#include<iostream>
#include<string>
#include<vector>

using namespace std;

int main(){
    int N,sum,tmp;
    int result = 0;
    vector<int> elem;

    cin >> N;
    cin >> sum;

    for(int i=0;i<N;i++){
        cin >> tmp;
        elem.push_back(tmp);
    }

    for(int i=0;i<N;i++){
        for(int j=i;j<N;j++){
            if((elem[i] + elem[j]) == sum){
                if(i != j){
                    result += 2;
                }else{
                    result += 1;
                }
            }
        }
    }

    cout << result <<endl;

    return 0;
}